Brainfuck is fully Turing complete, so by using it you can implement whatever you want. Of course it includes games, for examle 15 puzzle!
Run this with Brainfuck interpreters or compilers (which should be interactive).
If you're developing an interpreter or a compiler, let's try to use this for the operation test of it :)
This game's rules are the same as that of general 15 puzzles.
This game is completed on the following condition:
01 02 03 04
05 06 07 08
09 10 11 12
13 14 15 00
Input a character (one of wasd), then 00 is swapped for the corresponding number.
w: swapped for the one on the uppera: swapped for the one on the lefts: swapped for the one on the lowerd: swapped for the one on the right
The source code is here.